U.S. Pat. No. 4,638,529 to Katona discloses a straight handle gripping portion of a handle assembly with its ends supported in end caps, which are attached to a door. The handle gripping portion has a symmetrical cross section. In the preferred embodiment, the cross section of the handle gripping portion is substantially rectangular and has two parallel flanges formed in abutting relation during roll forming of the handle gripping portion. The specific position of the two parallel flanges depends on the direction in which the maximum force is to be exerted on the handle gripping portion.
One embodiment of U.S. Pat. No. 4,383,519 to Katona has a handle assembly including rectangular shape and end caps, which are mounted on a door, for receiving the ends of the handle gripping portion. The cross sectional shapes of the two aforesaid Katona patents are substantially the same.
Oven door handles are primarily used in the home to open and close the oven door. The load on the handle when used for this purpose is relatively light. However, the handle must be manufactured to withstand much greater loads because of the way the handle is used to move the range during the manufacturing process and when moving the range in the home, such as during installation and repair service. For example, frequently, a pushing force is applied to the handle to move the range.
In the prior art, oven door handles have typically been formed with a straight hollow bar supported at each end by handle end caps mounted on the oven door. Such bars have a tendency to bend when subjected to a pushing force. As the bar bends, at least one of the ends tends to disengage from the handle end cap. To withstand the above described greater loads applied to the handle, both the bar and the associated mounting structure must be heavy duty. For example, the bar needs to be reinforced, such as with additional material thickness to resist bending, and the end caps would be metal cast parts to provide sufficient structural strength.
The handle assembly of the present invention satisfactorily overcomes the aforementioned shortcomings of a straight handle gripping portion by forming the handle gripping portion with a selected radius of curvature. Curving of the handle gripping portion significantly increases its resistance to bending when subjected to a pushing force.
Additionally, by forming the handle gripping portion of the present invention with a non-rectangular and non-circular cross sectional shape with a greater portion of its cross sectional area on the door facing side of the handle, the strength of the handle gripping portion in the pulling direction is significantly improved.